Hippos are well-loved, cumbersome, rotund mammals famous for lounging around semi-submerged in muddy pools. Gregarious herbivores, they emerge after dusk from the water into the cool night air to graze on grass and plants before returning to the water at sunrise. They have huge mouths adapted for grazing as well as large, sharp tusks and jaws powerful enough to bite through crocodiles, small boats and even humans.

The common hippo, once found all over Africa, is now largely confined to South and East Africa, while its close relative, the mysterious pygmy hippo, is only found in the forests of Sierra Leone, West Africa. Hippos originated in Asia and share a common ancestry with whales. Until the last Ice Age, they were found across Europe, including Britain. The ancient civilizations of North Africa and the Middle East were familiar with the common hippo, as it was still plentiful along the Nile. To the Egyptians it was a revered deity while at the same time it was hunted for sport. While the Romans imported them into their circus spectacles in Rome, today the best place to see the common hippo is in its natural African environment.

Edgar Williams is Reader in Respiratory Science and Technology at the University of South Wales. He is author of Moon: Nature and Culture (2014) in Reaktion’s Earth series and Ostrich (2013) and Giraffe (2011) in Reaktion’s Animal series.